ST-segment elevation myocardial infarction patients are best treated with emergency percutaneous coronary intervention (PCI), while coronary microvascular dysfunction and obstruction (CMVO) are indicated by the absence or slowing of antegrade epicardial flow on angiography, resulting in suboptimal myocardial perfusion despite the lack of mechanical vascular obstruction. CMVO occurs in up to half of patients who undergo PCI for the first time and is associated with poor outcomes. This review summarizes the complex mechanisms leading to CMVO and elaborates on the changes observed at the organism, tissue, organ, cellular, and molecular levels. It also describes the current diagnostic methods and comprehensive treatment methods for CMVO.